Vortex generator



FIG. 1 is a front perspective view of a vortex generator showing our design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a right side view thereof (the left side view is a mirror image of the right side view);

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a vortex generator, as shown and described. 